Identity-based Public Auditing Research Articles

An improved identity-based public audit protocol for cloud storage

With the rapid development of informatization, a vast amount of data is continuously generated and accumulated, leading to the emergence of cloud storage services. However, data stored in the cloud is beyond the control of users, posing various security risks. Cloud data auditing technology enables the inspection of data integrity in the cloud without the necessity of data downloading. Among these, public auditing schemes have experienced rapid development due to their ability to avoid additional user auditing expenses. However, malicious third-party auditors can compromise data privacy. This paper proposes an improved identity-based cloud auditing scheme that can resist malicious auditors. This scheme is also constructed on an identity-based public auditing scheme using blockchain to prevent malicious auditing. We found the scheme is not secure because a malicious cloud server can forge authentication tags for outsourced data blocks, while our scheme has not these security flaws. Through security proofs and performance analysis, we further demonstrate that our scheme is secure and efficient. Additionally, our scheme has typical application scenarios.

PPADT: Privacy-Preserving Identity-Based Public Auditing With Efficient Data Transfer for Cloud-Based IoT Data

Public auditing is a significant technique in cloud-based IoT systems, which enables the verifier to check the integrity of IoT data stored in the cloud. Nowadays, data become a core property for owners. Once the data of one owner are sold to another one, the ownership of these data has to be transferred. However, the existing public auditing schemes with data transfer require all the authenticators corresponding to the transferred data to be transformed to the new ones for integrity auditing. It incurs significant computation cost because of re-computing the new authenticators for all transferred data, especially when a vast quantity of data is being transferred. In addition, the data privacy and the identity privacy of the data owner cannot be protected for the verifier in such schemes. Thus, how to achieve efficient data transfer and privacy protection are key challenges in public auditing with data transfer for cloud-based IoT data. In this paper, we propose a privacy-preserving identity-based public auditing scheme with efficient data transfer for cloud-based IoT data (PPADT). In PPADT, all the authenticators corresponding to the transferred data blocks do not need to be transformed. We only need to transform an aggregated authenticator in the integrity auditing phase. It means that the computation cost of data transfer is independent of the number of transferred data blocks. Furthermore, the data owner’s identity privacy can be ensured with the assistance of the private key generator. The data privacy can also be guaranteed by employing the random masking technique.

Identity-Based Public Auditing for Cloud Storage of Internet-of-Vehicles Data

The Internet of Vehicles (IoV) , with the help of cloud computing, can provide rich and powerful application services for vehicles and drivers by sharing and analysing various IoV data. However, how to ensure the integrity of IoV data with multiple sources and diversity outsourced in the cloud is still an open challenge. To address this concern, this paper first presents an identity-based public auditing scheme for cloud storage of IoV data, which can fully achieve the essential function and security requirements, such as classified auditing, multi-source auditing and privacy protection. Particularly, we design a new authenticated data structure, called data mapping table, to track the distribution of each type of IoV data to ensure fine and rapid audits. Moreover, our scheme can reduce the overheads for both the key management and the generation of block tags. We formally prove the security of the presented scheme and evaluate its performance by comprehensive comparisons with the state-of-the-art schemes designed for traditional scenarios. The theoretical analyses and experimental results demonstrate that our scheme can securely and efficiently realize public auditing for IoV data, and outperforms the previous ones in both the computation and communication overheads in most cases.

An identity-based public auditing protocol in cloud-assisted IoT

An identity-based public auditing protocol in cloud-assisted IoT

Identity-Based Public Auditing Scheme for Cloud Storage with Strong Key-Exposure Resilience

Secured storage system is a critical component in cloud computing. Cloud clients use cloud auditing schemes to verify the integrity of data stored in the cloud. But with the exposure of the auditing secret key to the Cloud Service Provider, cloud auditing becomes unsuccessful, however strong the auditing schemes may be. Therefore, it is essential to prevent the exposure of auditing secret keys, and even if it happens, it is necessary to minimize the damage caused. The existing cloud auditing schemes that are strongly resilient to key exposure are based on Public Key Infrastructure and so have challenges of certificate management/verification. These schemes also incur high computation time during integrity verification of the data blocks. The Identity-based schemes eliminate the usage of certificates but limit the damage due to key exposure, only in time periods earlier to the time period of the exposed key. Some of the key exposure resilient schemes do not provide support for batch auditing. In this paper, an Identity-based Provable Data Possession scheme is proposed. It protects the security of Identity-based cloud storage auditing in time periods both earlier and later to the time period of the exposed key. It also provides support for batch auditing. Analysis shows that the proposed scheme is resistant to the replace attack of the Cloud Service Provider, preserves the data privacy against the Third Party Auditor, and can efficiently verify the correctness of data.

Detailed analysis and improvement of an efficient and secure identity-based public auditing for dynamic outsourced data with proxy

For data owners of restricted cloud access with a delegated proxy, public auditing technology for cloud data integrity, plays critical roles in ensuring powerful productivity that flexible cloud services provide for their business. In order to address the scalability of data owners and storage clouds for secure public auditing, Yu et al. (2017) proposed an Identity-Based Public Auditing for Dynamic Outsourced Data with Proxy Processing (https://doi.org/10.3837/tiis.2017.10.019), which also overcomes complicated public key certificates management issue. In this article, we figure out that this scheme is vulnerable to data loss attack where clouds could pass integrity auditing without original data. Meanwhile, a threat of system security is demonstrated, i.e., any entities are able to recover proxy private keys and impersonate proxy to forge proxy tag, with two arbitrary data tag pairs of same data owner. To enable secure identity-based batch public auditing with proxy processing, we propose an improved scheme without these security flaws and prove its security under CDH hard problem in the random oracle model. With complexity analysis, our scheme shows better efficiency over identity-based proxy-oriented data uploading and remote data integrity checking in public cloud (ID-PUIC) in a single owner effort on a single cloud. Especially, we give the detailed analysis for how efficiently the attacks on Yu et al.’s scheme could be launched with an experiment, and demonstrate complete reduction on probability and time for proving security of our improved scheme. For potential application in big data storage, we first evaluate the error detection probability varying on number of auditing blocks, and then conduct detailed performance analysis by simulating our scheme and ID-PUIC scheme on the different number of data owners and storage clouds, with up to 106 data blocks.

Identity-based public auditing for cloud storage systems against malicious auditors via blockchain

Cloud storage systems provide users with convenient data storage services, which allow users to access and update outsourced data remotely. However, these cloud storage services do not guarantee the integrity of the data that users store in the cloud. Thus, public auditing is necessary, in which a third-party auditor (TPA) is delegated to audit the integrity of the outsourced data. This system allows users to enjoy on-demand cloud storage services without the burden of continually auditing their data integrity. However, certain TPAs might deviate from the public auditing protocol and/or collude with the cloud servers. In this article, we propose an identity-based public auditing (IBPA) scheme for cloud storage systems. In IBPA, the nonces in a blockchain are employed to construct unpredictable and easily verified challenge messages, thereby preventing the forging of auditing results by malicious TPAs to deceive users. Users need only to verify the TPAs auditing results in batches to ensure the integrity of their data that are stored in the cloud. A detailed security analysis shows that IBPA can preserve data integrity against various attacks. In addition, a comprehensive performance evaluation demonstrates that IBPA is feasible and efficient.

A new identity-based public auditing against malicious auditor in the cloud

With the development of cloud computing, the integrity of data is becoming increasingly important. The auditing schemes for data integrity allow data owners to verify the integrity of the data stored in an untrusted server. Most public auditing schemes are based on the public key infrastructure (PKI), which may lead to certificate management problems. Recently, an identity-based public auditing scheme was proposed and it could effectively reduce computation cost of auditors and solve certificate management problems. However, the scheme was proved to be insecure. In this paper, we consider the malicious auditor and propose a new identity-based public auditing against malicious auditor in the cloud computing. The new construction is proved to be secure by assuming the hardness of the computation Diffie-Hellman problem (CDHP). Finally, compared with the existing identity-based auditing scheme, our scheme is efficient and it reduces the computation overhead of the auditor.

Genuine and Secure Identity-Based Public Audit for the Stored Data in Healthcare Cloud.

Cloud storage has attracted more and more concern since it permits cloud users to save and employ the corresponding outsourced files at arbitrary time, with arbitrary facility and from arbitrary place. To make sure data integrality, numerous public auditing constructions have been presented. However, existing constructions mainly have built on the PKI. In these constructions, to achieve data integrality, the auditor first must authenticate the legality of PKC, which leads to a great burden for the auditor. To eliminate the verification of time-consuming certificate, in this work, we present an efficient identity-based public auditing proposal. Our construction is an identity-based data auditing system in the true sense in that the algorithm to calculate authentication signature is an identity-based signature algorithm. By extensive security evaluation and experimental testing, the consequences demonstrate that our proposal is safe and effective; it can efficiently hold back forgery attack and replay attack. Finally, compared with the two identity-based public auditing proposals, our proposal outperforms the two proposals under the condition of overall considering computational cost, communication overhead, and security strength.

Cryptanalysis of an identity-based public auditing protocol for cloud storage

Public verification of data integrity is crucial for promoting the serviceability of cloud storage systems. Recently, Tan and Jia (2014) proposed an identity-based public verification (NaEPASC) protocol for cloud data to simplify key management and alleviate the burden of check tasks. They claimed that NaEPASC enables a third-party auditor (TPA) to verify the integrity of outsourced data with high efficiency and security in a cloud computing environment. However, in this paper, we pinpoint that NaEPASC is vulnerable to the signature forgery attack in the setup phase; i.e., a malicious cloud server can forge a valid signature for an arbitrary data block by using two correct signatures. Moreover, we demonstrate that NaEPASC is subject to data privacy threats in the challenge phase; i.e., an external attacker acting as a TPA can reveal the content of outsourced data. The analysis shows that NaEPASC is not secure in the data verification process. Therefore, our work is helpful for cryptographers and engineers to design and implement more secure and efficient identity-based public auditing schemes for cloud storage.

Efficient and Secure Identity-Based Public Auditing for Dynamic Outsourced Data with Proxy

Cloud storage becomes a new trend that more and more users move their data to cloud storage servers (CSSs). To ensure the security of cloud storage, many cloud auditing schemes are proposed to check the integrity of users’ cloud data. However, most of them are based on public key infrastructure, which leads to complex certificates management and verification. Besides, most existing auditing schemes are inefficient when user uploads a large amount of data or a third party auditor (TPA) performs auditing for multiple users’ data on different CSSs. To overcome these problems, in this paper, we propose an efficient and secure auditing scheme based on identity-based cryptography. To relieve user’s computation burden, we introduce a proxy, which is delegated to generate and upload homomorphic verifiable tags for user. We extend our auditing scheme to support auditing for dynamic data operations. We further extend it to support batch auditing in multiple users and multiple CSSs setting, which is practical and efficient in large scale cloud storage system. Extensive security analysis shows that our scheme is provably secure in random oracle model. Performance analysis demonstrates that our scheme is highly efficient, especially reducing the computation cost of proxy and TPA.

Insecurity of an identity-based public auditing protocol for the outsourced data in cloud storage

Public auditing protocol is very significant for implementing secure cloud storage since it can be used to check the integrity of the data stored in the cloud without downloading them. Recently, Zhang and Dong presented an identity-based public auditing (IBPA) protocol using the bilinear pairing and claimed that their protocol is provably secure in the random oracle model. Through proposing two concrete attacks, we demonstrate that the adversary against Zhang-Dong’s protocol can break the data integrity without being found by the auditor. The analysis shows that their protocol is not secure for the cloud storage.